1. Field of the Invention
This invention relates to a method of performing the destructive distillation of hydrocarbonaceous materials such as coal, oil shale, tar sands, wood, etc. to obtain an upgraded distillate therefrom.
2. Background of the Invention
Formation of asphaltenes during the thermocracking of coal, oil shale, tar sands or the like, which asphaltenes are heat sensitive, non-distillable materials has been in the past and continues to be in the present a problem in maximizing distillate yield.
The production of asphaltenic polymeric material generally is attributed to the combination of organic radicals, that is, volatile free radicals in particular of the diene type formed by a retro Diels-Alder reaction.
This invention relates to a facile method of minimizing the formation of non-distillable polymeric by-products of destructive distillation by codistilling therewith dienophiles stable at the conditions of distillation, an example of such dienophiles being maleic anhydride.